1. Field of the Invention
The field of the invention comprises the determination of the molecular weight of a flowing gaseous material by means of a vortex tube.
2. Description of Prior Art
Heretofore, the molecular weight of a gas, as described in chemistry text books, has been determined in slow batch-type or single test procedures, one of which comprises measuring the volume of a weighed quantity of gas at an observed temperature and pressure, and using these data in the perfect-gas equation to calculate the molecular weight. Another comprises measuring the density, pressure, and temperature and calculating the molecular weight by aid of the perfect-gas equation rearranged to show the density. Still another is the Victor Meyer air displacement. No prior art flow methods capable of measuring the molecular weight of all gases or gas mixtures are known to applicant. Regarding the use of vortex tubes, applicant is aware of U.S. Pat. No. 3,165,146 which discloses a method for regulating the temperature of an instrument housing wherein the vortex tube is disposed within the housing, and temperature-controlled air is introduced to the tube. A thermocouple inside the housing and spaced some distance from the tube is used to sense the temperature in the housing and to influence the flow of temperature-controlled air thereto. The hot gas fraction of the vortex tube is removed from the housing while the cold gas fraction is discharged therein to cool the housing interior. This method is not concerned with molecular weight determinations.